文件下载暂停，永不恢复

Question

点击android下载按钮后。我们正在运行时创建PDF（appx 30页，生成需要4秒）。

下载进入PAUSED状态，它永远不会恢复

Download_Uri = Uri.parse("....url....");

DownloadManager.Request request = new DownloadManager.Request(Download_Uri);
request.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI | DownloadManager.Request.NETWORK_MOBILE);
request.setAllowedOverRoaming(false);
request.setTitle("GadgetSaint Downloading " + "Sample" + ".pdf");
request.setDescription("Downloading " );
request.setVisibleInDownloadsUi(true);
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "/GadgetSaint/"  + "/" + "Sample" + ".pdf");

refid = downloadManager.enqueue(request);